1. Field of the Invention
This invention relates generally to press apparatus and, more specifically, to an electromechanical press apparatus and method therefor that provides synchronized motion of a leadframe strip with motion of equipment for performing trimming or forming operations on the leadframe strip in a minimally sized press unit.
2. Description of the Related Art
Today, manufacturers are moving toward smaller, more compact machinery in order to reduce the size and cost of their manufacturing facilities. In the semiconductor industry, there has been a shift toward reducing the size of the various machines that perform such functions as wire bonding, plastic molding, post mold curing, dambar cutting, trimming, and forming. To further reduce the size of a semiconductor manufacturing facility, the trend has been to not only reduce the size of the production machinery but also to build machines in a modular manner that allows the machines to be quickly and easily coupled together in an in-line fashion.
With respect to the trimming and forming operations associated with semiconductor production, in general, there are two major steps in the process--moving the leadframe strip into position and performing the trimming or forming stroke. Combining machinery that can both move a leadframe strip into position and perform the trimming or forming operation into a unit of sufficiently small size without losing press power is a challenging problem. Prior art press type machines used for trimming and forming semiconductor packages have not been capable of providing sufficient power in a unit of sufficiently small size. Some prior art press units have employed hydraulic presses in an effort to maximize press power while minimizing the size of the unit. However, hydraulic presses are problematic for use in the clean room environment that is generally associated with the production of semiconductor packages. Therefore, there existed a need to provide an electromechanical type press used for trimming and forming semiconductor packages and their associated leadframe strips that provides maximum press power per unit volume of the machine.